Every fricking advert has either a black family or mixed race family. OTOH, there has never been a better time for black actors.
If you have to show diversity and there are only two or four people in the ad, what are you going to do?
I’m guessing the clients demand this in most instances. For one thing, they want to punch as many customer buttons as possible. For another, they live in dread that someone will complain about their “racist” advertising, perhaps with a formal complaint or perhaps on social media. All it takes is one crank and the social media zealots will take over.